Type 2 is the most common form of diabetes mellitus. It is a disease in which insulin is not as effective as in healthy people, and therefore more circulating insulin (hyperinsulinemia) is needed to keep blood sugar levels within the normal levels. This increase in needed insulin creates insulin resistance.
Insulin resistance occurs when body cells don’t allow glucose to enter easily and is worsened by overweight and physical inactivity. In addition to having insulin resistance, people with type 2 diabetes progressively lose the ability to produce insulin, as the beta cells in their pancreas gradually fail.
Both insulin resistance and beta cell failure worsen with time, so type 2 diabetes is usually a disease of middle-aged people; however, overweight and obese people of any age are at risk. A typical person with type 2 diabetes is overweight, physically inactive, and comes from a family with a history of diabetes or an ethnicity (African American, Hispanic/Latino, Native American, Asian American, or Pacific Islander) with a high risk for the disease.
Today, most people with type 2 diabetes are diagnosed from a screening blood test before the disease becomes clinically symptomatic. Diagnosis of diabetes mellitus is made by any one of these approved blood tests:
- A fasting plasma glucose level >126 mg/dl documented on two different days
- A random plasma glucose level >200 mg/dl along with classic symptoms of diabetes
- A 2-hour oral glucose-tolerance test >200 mg/dl after ingesting 75 g of glucose documented on two different days
- An A1c > 6.5% (ADA, 2015)
Chronic hyperglycemia damages tissues, and the primary goal of people with diabetes is to keep episodes of hyperglycemia to a minimum. Regulation of blood glucose levels is called glycemic control. In general, people with type 2 diabetes have three target measurements for their degree of glycemic control: their fasting blood glucose levels should be 70 to 130 mg/dl, their long-term average A1c value should be < 6.5% and postprandial BG should be <180 mg/dl.
The initial management approach in type 2 diabetes is to maintain good glycemic control by adjusting lifestyle behaviors; specifically, by losing weight, increasing physical activity, and eating a healthier diet. Later, most patients with type 2 diabetes need the help of oral medications to avoid chronic hyperglycemia. The first medication is generally recommended to be metformin. As the disease progresses and their beta cells fail, many people with type 2 diabetes eventually need supplemental insulin.
Diabetes puts people at risk for macrovascular problems, particularly atherosclerotic cardiovascular disease, with an increased chance of heart attacks and strokes; therefore, a key part of the management of diabetes is to reduce any additional cardiovascular risk factors. People with type 2 diabetes should keep their blood pressures low (<130/80 mm Hg), they should eat high-fiber, low-fat diets, and they should keep their blood lipids in a heart-healthy range.
In addition to cardiovascular problems, patients with diabetes are prone to microvascular problems that damage eyes, kidneys, and nerves. People with diabetes also suffer from poor wound healing. Maintaining good glycemic control and a low blood pressure will reduce the tissue damage caused by microvascular diabetic problems.
People with diabetes must take extra care to avoid injuries, especially to their feet. Wounds, infections, and injuries cause more hospitalizations than for people without diabetes, and wounds and infections need to be treated early and aggressively. When they are sick or hurt, people with diabetes should consult with their health team.
The statistics of diabetes show a growing percentage of people with diabetes, prediabetes, and metabolic syndrome. When a person is discovered to have prediabetes, the progression to type 2 diabetes can often be delayed with the same treatments that are used for T2DM. People with prediabetes and diabetes are all encouraged to lose between 5% and 10% of their total body weight, increase their physical activity, reduce their caloric intake, reduce the fat in their diet, and eat more dietary fiber. For some people with prediabetes, adding an anti-diabetic medication such as metformin is also helpful.
Disease Management in Brief
Diagnosis of prediabetes
- FPG = 100–125 mg/dl (impaired fasting glucose) on two separate occasions or
- 2-hour plasma glucose level (after a 75-g glucose load) = 140–199 mg/dl (impaired glucose-tolerance) on two separate occasions
- A1c between 5.5% and 6.4%
Diagnosis of diabetes (by any 1 test)
- FPG >126 mg/dl (on separate days)
- Random plasma glucose >200 mg/dl with symptoms
- 2-hour plasma glucose level (after a 75-g glucose load) >200 mg/dl (repeated on a separate day)
- A1c > 6.5 confirmed by repeating on a different day
Diabetes Treatment Goals
- A1c 4 <6.5%
- FPG = 70–<130 mg/dl
- Peak PPG= <180 mg/dl
- Systolic <130 mmHg
- Diastolic <80 mmHg
Lipid profile (fasting)
- LDL cholesterol <100 mg/dl (<70 mg/dl when cardiovascular disease is already present)
- HDL cholesterol: men >40 mg/dl, women >50 mg/dl
- Triglycerides <150 mg/dl
- Each 3 to 6 months
- History: review diet, exercise, lifestyle, smoking, alcohol use
- Exam: check weight, blood pressure, feet, patient’s psychological health
- Labs: check A1c, self-monitored glucose records
- Medicines: review medicines, consider low-dose aspirin to prevent CVD
Add to annual check-up
- Exam: calculate BMI
- Labs: check serum creatinine, urine albumin/creatinine ratio
- Medications: flu shot, ensure patient had pneumococcal vaccination
CVD = cardiovascular disease
FPG = fasting plasma glucose
PPG = postprandial glucose
Source: ADA, 2015.
Putting It All Together: Case Scenario
Samuel Gonzalez, as you remember from our introductory scenario, is a 58-year old Hispanic male who comes for an initial physical exam after complaining of constant thirst, fatigue, blurred vision, and decreased sensation in his feet for 6 months. At his wife’s insistence, he hopes there is a pill he can take to stop the annoying symptoms. He is a construction worker and wants to feel better. He was told to bring labs before the physical exam.
Q: What is the information needed for the initial exam?
A: A thorough history can reveal risk factors and family history as risks for diabetes mellitus.
Q: What information should be obtained in the physical exam?
A: A thorough head to toe assessment should include an exam of all body systems, including the eyes for any indications of retinopathy, the feet to assess for poor healing wounds or changes in musculature. Because he has already indicated poor sensation in his feet, the clinician should test for neuropathy using a monofilament and tuning fork for sensation and vibration. All the classic vital signs of course are needed.
Samuel’s chart reveals the following:
Height: 65 inches
Weight: 186 lbs (84 kg)
BMI: 30.9 (obese)
Pertinent laboratory results
Total cholesterol 250 mg/dL
Dental teeth extraction from abscess
Father died from a heart attack and was a smoker
Alcohol use (1–2 beers after work daily)
Lisinopril 20 mg once daily
Known drug allergies
Rationale: The FBS is >126 mg/dL, with symptoms
A: Questions about erectile dysfunction, depression; desire for smoking cessation and DSME instruction should be pursued.
Mr. Gonzalez is not surprised to hear he has developed type 2 diabetes and admits that he has an older brother and uncle with T2DM. He said his wife does want him to stop smoking and he has tried on his own but can’t quit. He also admits to some instances of ED and just thought it was his age.
A: He should be referred to an optometrist, a smoking cessation program, and certified diabetes educator for DSME. The clinician warns him to “stop smoking, lose weight, exercise, and don’t eat so much.” Because of his existing symptoms and risk factors, the physician also puts him on oral metformin 500 mg bid and oral simvastatin 40 mg qd, and oral bupropion (Zyban) 150 mg bid for smoking cessation. He is told to return in 3 months for a followup after his DSME. A plan is developed to address his ED and probable retinopathy and neuropathy in 3 months after his body has had time to adjust to the medications and the goal of smoking cessation.
A point-of care-office lab test for A1c is completed and the result is 10.8%. He is given a booklet on diabetes with online resources and a referral to the DSME program covered by his insurance company.
A: Depending on his insurance coverage and allowable hours, the diabetes educator should focus on teaching him how to use a glucometer and discuss meal planning improvements. Although there are seven self-care management strategies to be covered, beginning with key survival skills is important. Teaching him how to use a glucometer will allow him self-feedback on all other behavior modifications he attempts (eg, meal planning, exercise). Followup or class teaching visits could focus on teaching the seven DSME topics, avoiding complications, and involving his wife.
A: The physician should review a recent cholesterol panel and an A1c to compare with the initial A1c and log book. Followup on blood pressure, smoking cessation, weight, progress with the DSME program, depression, and episodes of ED should be addressed. Followup visits for every 3 months during the first year would be appropriate, especially with acute problems. Annual exams would include, baseline ECG, fundoscopic eye exams, comprehensive lab work to measure liver and kidney function, a lipid panel, and encouragement to continue to see a dentist. Celebrating his progress and making him a partner with his medical goals are key to momentum toward positive lifestyle behaviors.